Anti-torpedo system

ABSTRACT

1. In an antitorpedo system of the character disclosed, in combination, a radio frequency bridge having a source of radio frequency power connected thereto, a line of reference arranged at a predetermined distance from the vessel and parallel thereto, said reference line comprising an antenna disposed beneath and in contact with the water and abeam the vessel, means for applying a radio frequency current from said source to the antenna, the ends of one of the arms of said bridge being connected to the hull of the vessel and to said antenna respectively said one arm including an electrically conductive path through the water between the antenna and said hull, means in at least one of the other arms for initially adjusting the bridge to an off balance condition, an output circuit for said bridge, a transformer in said output circuit, detector means operatively connected to the output of said transformer, a discharge tube having the control element thereof connected to the output of said detector means, the degree of initial unbalance of said bridge being insufficient to fire said tube, a plurality of explosive missiles, a plurality of guns aimed just beneath said line of reference for firing said missiles in the direction of the torpedo, and electroresponsive firing means on each of said guns operatively connected to the plate of said tube for firing the guns when a torpedo has approached said line of reference to a point substantially subjacent with respect thereto and thereby changed the impedance of the antenna circuit and the radio frequency current flowing therein sufficiently to fire said tube.

United States Patent 1191 Hicks 1 1 ANTl-TORPEDO SYSTEM Raymond M.Hicks, 4326 18th St.. N.W.. Washington, DC

[76] Inventor:

[52] US. Cl. 89/1 A; 89/41 SW [51] Int. Cl. F4lg 3/00 [58] Field 01Search 89/1 A. 41; 340/4; 102/16 T; 114/21. 21W

[56] References Cited UNITED STATES PATENTS 1.195.042 8/1916 Leon 102/161.548.024 8/1925 Cuntz 340/4 1.635.117 7/1927 Dunmore 340/4 1.689.292111/1928 O'Neill i r i 340/4 1.865.101 6/1932 Hammond. Jr. 114/21 W2.404.266 7/1946 Loughnan 340/4 2.513.279 7/1951] Bradley 89/412.668.512 2/1954 Klas 89/1 A Primary ExaminerBenjamin A. BorcheltASA/X16111 Emminer-Charles T. Jordan Armrney. Agent. or FirmR. S.Sciascia; .1. A. Cooke EXEMPLARY CLAIM I. In an antitorpedo system ofthe character disclosed. in combination. a radio frequency bridge havinga 1 1 Apr. 8, 1975 source of radio frequency power connected thereto. aline of reference arranged at a predetermined distance from the vesseland parallel thereto, said reference line comprising an antenna disposedbeneath and in contact with the water and abeam the vessel. means forapplying a radio frequency current from said source to the antenna. theends of one of the arms of said bridge being connected to the hull ofthe vessel and to said antenna respectively said one arm including anelectrically conductive path through the water between the antenna andsaid hull. means in at least one of the other arms for initiallyadjusting the bridge to an off balance condition. an output circuit forsaid bridge. a transformer in said output circuit. detector meansoperatively connected to the output of said transformer, a dischargetube having the control element thereof connected to the output of saiddetector means. the degree of initial unbalance of said bridge beinginsufficient to fire said tube. a plurality of explosive missiles. aplurality of guns aimed just beneath said line of reference for firingsaid missiles in the direction of the torpedo. and clectroresponsivefiring means on each of said guns operatively connected to the plate ofsaid tube for firing the guns when a torpedo has approached said line ofreference to a point substantially subjacent with respect thereto andthereby changed the impedance of the antenna circuit and the radiofrequency current flowing therein sufficiently to fire said tube.

3 Claims, 4 Drawing Figures PATENTEBAPR 81915 3 .875.844-

SHEET 1 0F 2 DETECTOR c PARATOR ECTOR INVENTOR R. M. HlCKS BY -@@/uJ-PATENTEDAPR 81975 FLEET 2 2 INVENTOR R. M. HICKS ATTOR Y5 ANTI-TORPEDOSYSTEM The invention described herein may be manufactured and used by orfor the Government of the U.S.A. for governmental purposes without thepayment of any royalties thereon or therefor This invention relates toan antitorpedo system and more particularly to a system for protecting avessel against torpedo attack by firing an explosive charge into thewater in the path of the oncoming torpedo from at least one gun ormortar discharge device on the vessel in response to a variation in ahigh frequency field set up within the water by an approaching torpedo.

In devices of this class heretofore devised. it has been the usualpractice to protect a vessel from torpedo attack by various barriersplaced about the vessel. bombs, explosive streamers and the likearranged within the water and similar devices. Such devices have notbeen altogether satisfactory in operation for the reason that the speedof travel of the modern torpedo has been greatly increased in recentyears and the tactical methods employed in attacking by torpedo both airand sea launched have greatly reduced the effectiveness of such devices.

It is a primary object of this invention. therefore. to provide a systemfor protecting a vessel from torpedo attack which possesses all oftheadvantages ofthe prior art devices and none of the foregoingdisadvantages. In accordance with a preferred embodiment of theinvention the presence of the oncoming torpedo is made manifest by achange in antenna current ofa radio frequency transmitting system inwhich a reference line comprising an antenna is arranged within thewater and a predetermined distance abeam the vessel and parallelthereto. This change in antenna current causes one or more of aplurality of guns. mortars. or other launching apparatus on the vesselto fire a missile having an explosive charge therein into the water justinside the ref erence line and in the direction from which the torpedois approaching when the torpedo has arrived at a predetermined distancefrom the vessel in closely spaced adjacency to the reference line. Thetorpedo is thus destroyed or disabled by the explosion of the missiledis charged from the vessel within the water and without theintervention of an operator, although, if desired. an operator could beemployed for controlling the discharge of the guns.

One of the objects of the present invention is to pro vide a system forprotecting a vessel from torpedo attack and which is controlled by aradio signal continuously transmitted through the water.

Another object is to provide a new and improved system of detecting anddestroying a torpedo upon approach to a vessel in which a salvo isautomatically fired into the water from the vessel in the path of theoncoming torpedo when the signal caused by the torpedo has beenmodulated to a predetermined degree.

Still another object is to provide a gun firing system for disabling anoncoming torpedo in which the guns may be fired selectively eithersingly or in salvos.

Other objects and many of the attendant advantages ofthis invention willbe readily appreciated as the same becomes better understood byreference to the following detailed description taken in connection withthe accompanying drawings in which:

FIG. 1 is an elevational view of a vessel employing the system of thepresent invention in accordance with a preferred embodiment thereof;

FIG. 2 is a plan view of the vessel of FIG. I showing a firingarrangement of the guns under control of an operator;

FIG. 3 is a circuit diagram ofa firing control arrangement of the gunsof the vessel in response to an underwater radio signal modulated by theoncoming torpedo; and

FIG. 4 is an alternative circuit diagram for automatically firing theguns when a continuously transmitted radio signal has been modulated bythe torpedo Referring now to the drawings for a more completeunderstanding of the invention and more particularyly to FIG. I thereofthere is shown thereon a vessel indicated generally by the numeral 10having a plurality of guns 11 mounted thereon. each of the guns beingadapted to fire an explosive shell 12 into the path of travel of anoncoming torpedo 13. The explosive shell I2 is provided with suitablemeans such, for example. as a reversed ogival nose (not shown) forcausing water entry upon contact with the water surface and a time delayfuze or the like for preventing the shell from exploding until the shellhas entered the water and reached a depth of submersion generallycorresponding to the running depth of the torpedo.

On FIG. 2 is shown a circuit arrangement suitable for use with thevessel 10 and adapted to fire selectively either one or a salvo of gunsII under the control of an operator. The system shown on FIG. 2comprises a plu rality of guns or mortars ll preferably pointed downwardly toward the surface of the water and of the type adapted to befired by an electrical impulse received over a firing circuit. Twoseparate systems are disclosed. one for the port and the other for thestarboard side ofthe vessel. For the purpose of descriptioncorresponding parts ofthe two systems have been designated by likenumerals of reference. The guns II on the port side of the vessel, forexample, are shown grouped into two groupsv The guns of the forwardgroup covering the area between the midpoint of the vessel and the boware connected together by a conductor 14 to which a battery 15 isapplied by operation ofswitches 16 or 17, as the case may be, theoperation of switch 16 to closed position causing the guns in thissection to fire. In a similar manner the guns 11 at the rear portion ofthe vessel are connected to switch 18 by conductor 19 whereby operationof switch I8 to a closed position causes the rear guns to fire.Conductor I9 is also connected to contact of switch 17. When switch 17is closed, both guns on the forward and rear positions of the port sideof the vessel are fired. The guns, it will be understood. may if desiredbe ofa repeating type such that repeated salvos therefrom are fired inquick successive order as long as any of the firing keys I6. 17 or 18are closed.

In similar manner corresponding switches 21, 22, and 23 are employed tocontrol the gun fire on the starbord side of the vessel.

Referring now to FIG. 3 there is shown thereon a gun fire control systemin which the intervention of an operator is not required. The systemcomprises a radio frequency bridge generally indicated by the numeral 24and having three arms, Z1. Z2, and Z3, the fourth arm comprising anantenna 25 connected thereto and arranged within the sea water and towedby the vessel from whence the circuit is completed by way of the seawater to ground 26 at the hull of the vessel. The bridge is suppliedwith a source of radio frequency RF substantially as shown and the armsZ1. Z2, and Z3 are adjusted in such manner that the bridge is normallyslightly off balance thereby to apply a small continuously alternatinghigh frequency current to the primary winding P of transformer 27, thesecondary winding S of which is connected in a well-known manner to arectifying detector. This arrangement provides a reference voltage tothe control element of the tube 28 of insufficient value to fire thetube. Preferably. though not necessarily. a grid leak resistance 29 isconnected between the control element of the tube and the cathode. Thecathode filament is heated in a conventional manner as shown and theplate of the tube is connected by conductor 31 to the guns ll. the platevoltage for the tube being supplied from battery 32 by way of resistance33.

The antenna is maintained outboard in predetermined spaced relation fromthe vessel in any convenient manner as by a paravane 20. HO. 1, a lineinterconnecting the paravane to the vessel and having a conductortherein for establishing an electrical connec' tion to the antenna.

ln operation when a torpedo approaches the vessel. FIG. and moves into aposition sufficiently near the antenna to change the impedance of thevariable arm of the bridge 24. the output of the bridge is changed andas the torpedo moves substantially to the position with respect to thevessel shown on FIG. 1. tube 28 fires thereby firing the guns llcontrolled thereby.

In FIG. 4 is shown an alternative firing control system suitable for usewith the instant invention in which the secondary winding Softransformer 27 is connected to the input of a comparator detector. Anair core transformer 34 is employed with this arrangement. the primarywinding P of which is connected across the source of radio frequencysignals and the secondary winding S is connected to the comparatordetector as shown. When employed with the underwater antenna 25 theradio frequency is set at an optimal value. Variations in impedancebetween antenna 25 and the hull of the vessel caused by modulation ofthe radio field by the oncoming torpedo moving into the vicinity thereofcauses tube 28 to discharge and fire the guns ll.

The detector connected to the secondary winding S of transformer 27 isresponsive to rapid changes in impedance of the antenna circuit such asthose caused by the approach of a torpedo and is relatively unresponsive to slow changes in the impedance of the antenna frequency such asmay be caused by movement of the antenna with respect to the vessel oras the result of wave motion.

When employing automatic control for the firing of the guns. theexplosive shells 12 are fired at the topedo in response to a change ofpredetermined character in the impedance of the antenna circuitregardless of whether the firing circuit of FIG. 3 or FIG. 4 isemployed.

While the invention has been described with particularity. withreference to guns for firing the explosive shells. it will be understoodthat this is by way of example only and other instrumentalities andmeans may be employed for projecting the missile such, for example. ascompressed air. springs, mortars. rocket launchers. and the like.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. In an antitorpedo system of the character dis closed. in combination.a radio frequency bridge having a source of radio frequency powerconnected thereto. a line of reference arranged at a predetermineddistance from the vessel and parallel thereto. said reference linecomprising an antenna disposed beneath and in contact with the water andabeam the ves sel. means for applying a radio frequency current fromsaid source to the antenna. the ends of one of the arms of said bridgebeing connected to the hull of the vessel and to said antennarespectively said one arm including an electrically conductive paththrough the water be tween the antenna and said hull. means in at leastone of the other arms for initially adjusting the bridge to an offbalance condition, an output circuit for said bridge. a transformer insaid output circuit. detector means op eratively connected to the outputof said transformer. a discharge tube having the control element thereofconnected to the output of said detector means. the degree of initialunbalance of said bridge being insuffi cient to fire said tube. aplurality of explosive missiles. a plurality of guns aimed just beneathsaid line of refer ence for firing said missiles in the direction of thetorpedo, and electroresponsive firing means on each of said gunsoperatively connected to the plate of said tube for firing the guns whena torpedo has approached said line of reference to a point substantiallysubjacent with respect thereto and thereby changed the imped ance of theantenna circuit and the radio frequency current flowing thereinsufficiently to fire said tube.

2. A system for protecting a vessel from torpedo attack comprising aradio frequency bridge. a line of reference arranged at a predetermineddistance from the vessel and parallel thereto. said reference linecomprising an underwater antenna disposed beneath the surface of thewater in contact therewith and carried by said vessel in abeam relationtherewith. means for ap plying a radio frequency current to the antenna,said bridge having the ends of one arm thereof connected to the hull ofthe vessel and to said antenna respectively said one arm including anelectrically conductive path through the water and said hull. aplurality ofexplosive charges. means for directing and suddenlypropelling the charges through the air outboard of the vessel and towardsaid line of reference in a direction such that the charges enter thewater just inside the line of reference and ahead of the torpedo. andelectroresponsive means operatively connected to said bridge foractuating said charge propelling means when said bridge is unbalanced bya predetermined change in the impedance of the antenna circuit and theradio frequency current flowing therein caused by said torpedo.

3. In a system for protecting a vessel from torpedo attack, incombination. a line of reference arranged at a predetermined distancefrom the vessel and parallel thereto, said reference line comprising anantenna disposed beneath the surface of the water and connected to saidvessel in a manner to be towed abeam thereby. means including an antennacircuit for applying a radio frequency current to said antennacontinuously. the hull of the vessel and the water between said antennaand said hull being included in the path of said current.

6 torpedo moves into close adjacency with said line of reference forgenerating a firing signal, and means operatively connected to saidsignal generating means for actuating the weapon hurling means inresponse to said firing signal.

1. In an antitorpedo system of the character disclosed, in combination,a radio frequency bridge having a source of radio frequency powerconnected thereto, a line of reference arranged at a predetermineddistance from the vessel and parallel thereto, said reference linecomprising an antenna disposed beneath and in contact with the water andabeam the vessel, means for applying a radio frequency current from saidsource to the antenna, the ends of one of the arms of said bridge beingconnected to the hull of the vessel and to said antenna respectivelysaid one arm including an electrically conductive path through the waterbetween the antenna and said hull, means in at least one of the otherarms for initially adjusting the bridge to an off balance condition, anoutput circuit for said bridge, a transformer in said output circuit,detector means operatively connected to the output of said transformer,a discharge tube having the control element thereof connected to theoutput of said detector means, the degree of initial unbalance of saidbridge being insufficient to fire said tube, a plurality of explosivemissiles, a plurality of guns aimed just beneath said line of referencefor firing said missiles in the direction of the torpedo, andelectroresponsive firing means on each of said guns operativelyconnected to the plate of said tube for firing the guns when a torpedohas approached said line of reference to a point substantially subjacentwith respect thereto and thereby changed the impedance of the antennacircuit and the radio frequency current flowing therein sufficiently tofire said tube.
 2. A system for protecting a vessel from torpedo attackcomprising a radio frequency bridge, a line of reference arranged at apredetermined distance from the vessel and parallel thereto, saidreference line comprising an underwater antenna disposed beneath thesurface of the water in contact therewith and carried by said vessel inabeam relation therewith, means for applying a radio frequency currentto the antenna, said bridge having the ends of one arm thereof connectedto the hull of the vessel and to said antenna respectively said one armincluding an electrically conductive path through the water and saidhull, a plurality of explosive charges, means for directing and suddenlypropelling the charges through the air outboard of the vessel and towardsaid line of reference in a direction such that the charges enter thewater just inside the line of reference and ahead of the torpedo, andelectroresponsive means operatively connected to said bridge foractuating said charge propelling means when said bridge is unbalanced bya predetermined change in the impedance of the antenna circuit and theradio frequency current flowing therein caused by said torpedo.
 3. In asystem for protecting a vessel from torpedo attack, in combination, aline of reference arranged at a predetermined distance from the vesseland parallel thereto, said reference line comprising an antenna disposedbeneath the surface of the water and connected to said vessel in amanner to be towed abeam thereby, means including an antenna circuit forapplying a radio frequency current to said antenna continuously, thehull of the vessel and the water between said antenna and said hullbeing included in the path of said current, a plurality of explosivetorpedo destroying weapons on said vessel, means for hurling saidweapons through the air in the direction from which the torpedo isapproaching whereby the weapons enter the water just inside said line ofreference and ahead of the oncoming torpedo, means responsive to achange in the radio frequency current flowing in the antenna circuit asthe torpedo moves into close adjacency with said line of reference forgenerating a firing signal, and means operatively connected to saidsignal generating means for actuating the weapon hurling means inresponse to said firing signal.